title: A novel approach to evaluate the effect of medicaments used in endodontic regeneration on root canal surface indentation.
abstract: OBJECTIVE
  The aim of this study was to investigate the capability of a novel reference point indentation apparatus to test the indentation properties of root canal surface dentine treated with three intracanal medicaments used in endodontic regeneration.
  
  
  METHODS
  Immature human premolars were selected (n = 22). Four specimens were obtained from each root and randomly assigned to three treatment groups and a control group. Each specimen was exposed to one of the three treatment pastes (triple antibiotic (TAP), double antibiotic (DAP), or calcium hydroxide (Ca(OH)2)) or neutral deionized water (control) for 1 or 4 weeks. After each time interval, the indentation properties of the root canal dentine surfaces were measured using a BioDent reference point indenter. Two-way ANOVA and Fisher's protected least significant differences were used for statistical analyses.
  
  
  RESULTS
  Significant differences in indentation parameters and estimated hardness between all groups at both time points were found. TAP-treated dentine had the highest significant indentation parameters, followed by DAP-treated dentine, untreated control dentine, and Ca(OH)2-treated dentine, respectively. Furthermore, TAP-treated dentine had the lowest significant estimated hardness, followed by DAP-treated dentine, untreated control dentine, and Ca(OH)2-treated dentine, respectively.
  
  
  CONCLUSIONS
  BioDent reference point indenter was able to detect significant differences in indentation properties of root canal dentine treated with various medicaments.
  
  
  CONCLUSIONS
  The use of a reference point indenter is a promising approach to characterize the indentation properties of root canal surfaces without any surface modification. This might provide an in vitro mechanical measurement that is more representative of the actual clinical situation.
authors.affiliation: Department of Restorative Dentistry, Division of Dental Biomaterials, Indiana University School of Dentistry, 1121W. Michigan St., Indianapolis, IN, 46202, USA, gyassen@iupui.edu.
authors.forename: Ghaeth H
authors.initials: GH
authors.lastname: Yassen
authors.forename: Tien-Min G
authors.initials: TM
authors.lastname: Chu
authors.forename: Maxime A
authors.initials: MA
authors.lastname: Gallant
authors.forename: Matthew R
authors.initials: MR
authors.lastname: Allen
authors.forename: Mychel M
authors.initials: MM
authors.lastname: Vail
authors.forename: Peter E
authors.initials: PE
authors.lastname: Murray
authors.forename: Jeffrey A
authors.initials: JA
authors.lastname: Platt
mesh_terms: D003786:Dental Pulp Cavity / Q000033:anatomy & histology*; D004708:Endodontics; D006801:Humans; D008855:Microscopy, Electron, Scanning; D012390:Root Canal Therapy